Spiral or winding staircase with wooden steps and metal newel

ABSTRACT

A device for a winding staircase having woden steps stabilized on a newel and with each other by muffle spacers. The newel is fitted with elastic tightening means which keep the muffle spacers pressed against the steps to develop an elastic reaction which compensates for loosening caused by step shrinkage. Elastic tightening means are also provided for vertical connections between the outer ends of the steps, as well as in all other handrail balusters, along the outer contour of the staircase.

United States Patent [72] Inventor Verderio Giuseppe Via Padana Superiore l, Gessate, Italy [21] Appl. No. 809,767 [22] Filed Mar. 24, 1969 [45] Patented June 22, 1971 {32] Priority Apr. 1, 1968 [33] Italy [31 I 14,675A/68 [54] SPIRAL 0R WINDING STAIRCASE WITH WOODEN STEPS AND METAL NEWEL 4 Claims, 4 Drawing Figs.

[52] US. Cl 52/187 [51] Int. Cl E041 11/00 [50] Field oISeareh... 52/187, 188,191,182,183,227,573

[56] References Cited UNITED STATES PATENTS 533,700 2/1895 Boyd et al 52/227 X 1,105,877 8/1914 Buellesbach. 52/183 1,783,383 12/1930 Montrief 52/573 X Primary ExaminerFrank L. Abbott Assistant ExaminerSame D. Burke, lll Attorney-Irving M. Weiner ABSTRACT: A device for a winding staircase having woden stepsstabilized on a newel and with each other by muffle spacers. The newel is fitted with elastic tightening means which keep the muffle spacers pressed against the steps to develop an elastic reaction which compensates for loosening caused by step shrinkage. Elastic tightening means are also,

provided for vertical connections between the outer ends of the steps, as well as in all other handrail balusters, along the outer contour of the staircase.

SPIRAL OR WINDING STAIRCASE WITII WOODEN STEPS AND METAL NEWEL The present invention relates to a device which may be used, for example, in a spiral or winding staircase having wooden steps and a metal newel, which newel may be sheated or not with wood.

SUMMARY OF THE INVENTION The invention deals with a device associated with the vertical newel by which steps are supported, as well as the stabilization and connection of such steps both with the newel and with each other. In a broader sense, the invention relates to a novel device or mechanism for stabilizing the distance between at least two relatively fixed members, such as steps or newel base attachments.

It is known that in winding staircases the wooden steps are stabilized and connected with a tubular supporting newel by means of metal muffle attachments having a length which is nearly equal to the vertical spacing, i.e., to the rise of the steps. In fact, each step, i.e., the fiat element that serves as a support for the feet, is stabilized between two of such muffles with the interposition, on both upper and lower ends thereof, of two annular flanges having a constant thickness and inner and outer diameters which are smaller and greater, respectively, than the muffle outer diameter. Due to aesthetical reasons, in some types of staircases, both the step spacing elements and the lower ends of the balusters are sheathed with tubular wooden elements.

It may occur that, due to the shrinkage of wood, the thickness of the step is reduced even if by a very small amount. However, such shrinkages, when summed up, result in an slackening and/or loosening of spacers in an axial direction with consequent shaking of the whole structure. Because of such undesired settlings and loosenings, there is needed a firm connection of steps both with the newel and with each other.

The main purpose of this invention is the provision of a device or means which, though of simple design and of easy realization, will positively prevent the abovestated ill effects, i.e., the loosening and slackening of the structural elements of a winding staircase.

In a broad sense, the present invention provides a device for stabilizing the distance between at least two relatively fixed numbers, such as a step or base attachment of a spiral staircase. The device includes, in combination, an elongated element, such as a step-supporting newel or a tubular spacer, arranged substantially perpendicular to the relatively fixed members. There is also included a first elastic tightening means, such as a cup spring, interconnected between at least a portion of the elongated element and at least one of the relatively fixed members. The elastic tightening means counteracts and compensates for loosening forces exerted on the relatively fixed members and on other portions of the device, and for shrinkage and other dimension variations of the relatively fixed members and of other portions of the device.

The inventive device is especially suited for use in a winding staircase of the type wherein the steps are stabilized both on a tubular newel and with each other by muffle spacers. A vital feature of the invention is elastic tightening means fitted on at least one end of the newel, and by which the muffle spacers are forced against the intervening steps, thus developing an elastic reaction to compensate for the axial shiftings caused by the shrinkage of wooden steps. Similar elastic tightening means may be fitted also in the vertical connection of single steps, all along the outer contour of the winding staircase.

The elastic tightening means preferably comprises resilient means or springs, e.g., of the cup or like types. Such spring may be fitted at the lower end of the newel, interposed between the base attachment thereof and the first annular member under the lowest mufile spacer.

The loosening of steps may be caused, apart from the shrinkage of wooden material, also by the operating stresses. Repeated and heavy stresses may result in an impression of the metal muffle spacers into the wooden steps, thus contributing to the above-mentioned shaking of the whole structure.

All such drawbacks are obviated by the elastic compensation system and device according to this invention, which will be described below.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The drawings represent only two possible embodiments of the invention. In the drawings: FIGS. land la are vertical axial sections of a nonwooden sheathed newel of a winding staircase, showing how the steps are connected with the newel.

FIG. 2 is a vertical axial section showing how two successive steps are connected with each other on their outer ends; and

FIG. 3 is a vertical axial section similar to that of FIGS. 1 and la, but showing a staircase having a wooden sheathed newel.

DETAILED DESCRIPTION With reference to the drawings, A is an elongated element in the form of a tubular cylindric newel and B is a relatively fixed member or step, which may be fabricated from wood or other materials, supported by the newel.

Welded to bottom of newel A is a relatively fixed member or disc I acting as a base attachment, and by which the newel A is firmly secured to the floor by cramps 2 which are let into the concrete or like foundation.

Slipped onto the newel A are muffle spacers C having an inner diameter slightly larger than the outer diameter of newel A. Secured to either end of each muffle spacer C is an annular member 3 which also has an inner diameter slightly larger than the outer diameter of newel A so that it can be thus slipped thereon. The annular member 3 is formed with an annular setback 30 (see FIG. la) against which abuts an end of a muffle spacer C. The steps B have an elongated triangular shape and an inwardly directed vertex which is formed with a bore similar to that of muffle spacers C, and can therefore be slipped on the newel. Each step B is locked between two muffle spacers C with the interposition of two annular members 3.

According to the all muffle spacers C are tightly maintained togetherthus counteracting any possible loosening due to the shrinkage of wooden steps B-by the pressure of at least one spring fitted on one newel end. In the considered embodiment, use is made of two resilient means or spring cups, one of which is fitted near the newel base, while the other is fitted near the newel top.

The first cup spring M, is fitted between the base disc or attachment 2 and the annular member 3, which is placed below the lowest muffle spacer C,, while the second cup spring is placed on the newel top between a plate 4 with an aperture 4a and a washer 5 accommodated in a recess 6 that is formed in the top plane 7. The washer 5 is vertically adjustable to adjust the tension of spring M, by means of a threaded shank 8 which can be screwed into an inside threaded bore of a stopper 9 welded on top of newel A.

All the steps are kept tightly clamped between the muffle spacers and appertaining annular members by the concomitant action of both springs M, and M whereby the steps are stabilized notwithstanding the axial shiftings of metal muffle spacers C due to decrease, or at any rate to the changes, in the thickness of steps B. In fact, the axial thrust exerted by the springs, and by which the muffle spacers can be slightly shifted, is adapted to compensate for the changes in the thickness of the steps, whereby the steps are always maintained firmly stabilized against the newel A.

Similar means are provided for winding vertical connection all along the outer contour of the winding staircase. In either outer corners of each step B, a connection with the next step is provided for, and more precisely the fore corner (as seen when going upstairs) of each step is connected with the step below, while the rear comer is connected with the step above.

One of such connections is shown in FIG. 2. The connection is established by a a newel or central rod 10 and a tubular muffle spacer I! having both its ends fitted with annular members l2, similar to members 3, each step B being stabilized between two of said members 12.

According to the invention, the connection of two successive steps is established by the rod having a threaded lower end 10a, whereon a tubular nut 13 formed with a flat head 13a is screwed. A spring M is interposed between the head 13a and the lower side of step B. Abutting against the upper side of the step above is a washer 14 through which the rod 10 is threaded, and which therefore cooperates with the action of spring M3.

The rod 10 extends through all the steps, thereby forming one of the handrail balusters; obviously no muffle spacers 11 are needed for the task of the other balusters.

The tension of spring M can be adjusted at will by more or less screwing the nut 13 on the rod 10, which can be done by a wrench that is engaged into the holes 13b of head 130. Even all other rods 10, acting as handrail balusters only, and not as a connection between the steps, are fitted with a nut 13-1311 and a spring M a at their lower ends.

Fitted at the bottom end of newel A is a wooden cover 15 (see FIG. 1a) by which the springM,, as well as the metal disc 1 welded to said newel A, are covered.

A newel with the related steps, forming part of a woodsheathed staircase, is shown in FIG. 3. All components are similar to those as previously described and shown in FIGS. 1 and la, except that the muffle spacers C, are in contact with the newel A, i.e., their inside diameter is just sufficient to allow the muffle spacers to be slipped on the newel, while the members 3' fitted on either end of each Spacer C, consist of rings having a rectangular cross section, and tubular wooden elements D are provided by which the spacers C, are covered. Both ends of the wooden elements are stepped down with a corresponding increase in the inside diameter thereof to accommodate the members 3 which have a diameter greater than that of spacers C,. The springs M, and M, are similar to the above described ones, and are also similarly seated. The lower end portion D of the lowest member D is engaged into an annular slit as provided therefor in the base cover 15.

The embodiments of the invention in which I claim an exelusive property or privilege are defined as follows:

1. In a winding stair case structure, a rigidly mounted newel,

a plurality of steps apertured to receive said newel,

a plurality of tubular spacers interposed coaxially between said steps and surrounding said newel,

means between said spacers and said newel displaceable coaxially of said newel to urge said spacers and steps together, and

means cooperable with said newel to hold said resilient means displaced.

2. In a winding staircase structure as defined by Claim l wherein said resilient means is within at least one of said steps.

3. In a winding staircase structure as defined by Claim 2 wherein an adjustment member to effect displacement of said resilient means extends through said one step into abutting relation with said resilient means and having a threaded connection with said rigid newel.

4. In a winding staircase structure as defined by claim 1 wherein said resilient means includes a lower resilient member supporting said tubular spacers and steps, a nut extending into the lowermost step and supporting said lower resilient member, and a a rotatable newel extending through said spacers and steps and having a threaded connection with said nut to displace said resilient means. 

1. In a winding stair case structure, a rigidly mounted newel, a plurality of steps Apertured to receive said newel, a plurality of tubular spacers interposed coaxially between said steps and surrounding said newel, means between said spacers and said newel displaceable coaxially of said newel to urge said spacers and steps together, and means cooperable with said newel to hold said resilient means displaced.
 2. In a winding staircase structure as defined by Claim l wherein said resilient means is within at least one of said steps.
 3. In a winding staircase structure as defined by Claim 2 wherein an adjustment member to effect displacement of said resilient means extends through said one step into abutting relation with said resilient means and having a threaded connection with said rigid newel.
 4. In a winding staircase structure as defined by claim 1 wherein said resilient means includes a lower resilient member supporting said tubular spacers and steps, a nut extending into the lowermost step and supporting said lower resilient member, and a a rotatable newel extending through said spacers and steps and having a threaded connection with said nut to displace said resilient means. 